Past exam of the mathematics course of the University of Cambridge 2023 ii Paper 4 10D a Solution Created 2026-09-24 Updated 2026-09-25
Let the unknown qubit be . Alice holds this qubit and her half of the shared Bell state , while Bob holds the other half.
Alice performs a measurement of her two qubits in the Bell basis and sends the two-bit outcome to Bob through the classical channel. For the shared state , the teleportation with the psi-plus Bell state correction table isup to physically irrelevant global phases. Here and are the Pauli X gate and Pauli Z gate. After the indicated correction, Bob's qubit is . This is quantum teleportation; no physical copy of the unknown qubit is sent.